Insight into the transcriptional regulation of Msn2 required for conidiation, multi-stress responses and virulence of two entomopathogenic fungi
Insight into the transcriptional regulation of Msn2 required for conidiation, multi-stress responses and virulence of two entomopathogenic fungi
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深入了解两种昆虫病原真菌分生孢子形成、多重应激反应和毒力所需的 Msn2 转录调控
DOI：
10.1016/j.fgb.2013.02.008
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发表时间：
2013-05-01
影响因子：
3
通讯作者：
Feng, Ming-Guang
中科院分区：
文献类型：
--
作者：
Liu, Qian;Ying, Sheng-Hua;Feng, Ming-Guang
一些真菌中的MSN2/4转录因子在毒力和细胞应激反应中没有作用。在此，我们发现MSN2同源基因的转录调控对球孢白僵菌和罗伯茨绿僵菌的分生、毒力和多重胁迫反应至关重要，而这两个细菌缺乏MSN4同源基因。与所有表型相似的野生型和互补型菌株相比，Delta Bbmsn 2和Delta Mr msn 2在分生孢子产量和致病力方面存在显著缺陷(减分生40%)和致病力(减产25%左右)。在菌落生长过程中，两个Delta突变体都失去了对高渗透压、氧化、多菌灵、细胞壁扰动和34℃高温的耐受性的20%-65%。它们的分生孢子对氧化、高渗、45℃湿热胁迫和UV-B辐射的耐受性也显著降低(18-41%)。伴随着缺陷表型，几个与分生孢子和毒力相关的基因在Delta Bbms2和Delta mms2中受到了极大的抑制。此外，在氧化胁迫下，Delta Bbms2与野生型相比，在转录本中的差异表达基因增加了3%，而在热休克下，差异表达基因减少了12%，而Delta Mr msn2的转录本中的差异表达基因则减少了12%。许多应激反应效应基因和细胞信号因子显著下调。综上所述，这两种昆虫病原体可能进化出了一些不同的应激反应机制，MSN2微调了这一机制，突显了MSN2同源基因对丝状真菌的生物学意义。(C)2013 Elsevier Inc.保留所有权利。
Msn2/4 transcription factors in some fungi have null effects on virulence and cellular stress responses. Here we found that the transcriptional regulation of Msn2 orthologs is vital for the conidiation, virulence and multi-stress responses of Beauveria bassiana (Bb) and Metarhizium robertsii (Mr), which lack Msn4 orthologs. Compared to wild-type and complemented strains of each fungus with all similar phenotypes, Delta Bbmsn2 and Delta Mrmsn2 showed remarkable defects in conidial yield (similar to 40% decrease) and virulence (similar to 25% decrease). Both delta mutants lost 20-65% of their tolerances to hyperosmolarity, oxidation, carbendazim, cell wall perturbing and high temperature at 34 degrees C during colony growth. Their conidia were also significantly (18-41%) less tolerant to oxidation, hyperosmolarity, wet-heat stress at 45 degrees C and UV-B irradiation. Accompanied with the defective phenotypes, several conidiation- and virulence-associated genes were greatly repressed in Delta Bbmsn2 and Delta Mrmsn2. Moreover, differentially expressed genes in the transcriptomes of Delta Bbmsn2 versus wild type were similar to 3% more under oxidative stress, but similar to 12% fewer under heat shock, than those in the Delta Mrmsn2 counterparts. Many stress-responsive effector genes and cellular signaling factors were remarkably downregulated. Taken together, the two entomopathogens could have evolved somewhat distinct stress-responsive mechanisms finely tuned by Msn2, highlighting the biological significance of Msn2 orthologs for filamentous fungi. (C) 2013 Elsevier Inc. All rights reserved.